The present invention relates to a door shutter sliding along a guide groove of a device and bendable in a sliding direction.
As shown in Patent Documents 1 and 2, the door shutter includes a main body bendable in the sliding direction and closing an opening of the device; and a projecting portion provided on both sides of a width direction of the main body and fitted into the guide groove of the device.
As shown in FIG. 13(a), the structure of Patent Document 1 opens and closes an upper opening of a device 50 by a shutter 53. The device 50 consists of a main body 51 forming a housing portion 51 a whose upper side is open; and a cover 52 with an opening 52 a covering the main body 51 from above. The shutter 53 includes a main body 54 bendable through thin-walled portions 54a; and a number of projecting portions 55 projecting to both sides of the main body 54. In a state where each projecting portion 55 is fitted into both sides of the guide groove provided between the main body 51 and the cover 52, the shutter 53 slides to the lower left in the figure and turns to an open position from a closing position where the upper opening of the housing portion 51a is closed.
On the other hand, as shown in FIG. 13(b), the structure of Patent Document 2 opens and closes the upper opening of a device 59 by a shutter 61. The device 59 forms a guide groove 62 in both inner side wall portions wherein a container main body 60 forms the upper opening. The shutter 61 consists of a core material with strengthening ribs in a width direction and a surface material covering an upper surface. The shutter 61 includes a number of projecting portions and warp protection pieces 61a on both sides. In a state where the projecting portions and warp protection pieces 61a are fitted into the guide groove 62, the shutter 61 slides to the lower right in the figure and turns to the open position from the closing position wherein the upper opening of the container main body 60 is blocked.
Patent Reference 1: Japanese Patent Publication (Tokkai) No. S54-33442.
Patent Reference 2: Japanese Patent Publication (Tokkai) No. H8-192685.
In the structure of Patent Documents 1 and 2, upper edges of the both inner side wall portions of the opening of the device have the same height. However, with respect to a device installation portion, the upper edges of both inner side wall portions of the opening of the device may have the different heights, or the upper edges of the both inner side wall portions of the opening of the installation portion attaching the device may have different heights. Moreover, the guide groove may include a curve portion in a ditch direction.
In this case, in the structure of a conventional shutter, both guide grooves have different heights, or a line connecting both guide grooves slightly tilts toward a horizontal line, so that it is difficult to settle a sliding track of the shutter within the size between the both guide grooves. Also, in the structure of the Patent Documents 1 and 2, the shutter is made of resin which excels in formability and lightness in weight. Also, the main body is bent in the sliding direction depending on the way of formation of a thin-walled portion in a width direction or installation of the strengthening ribs. However, it is difficult to be satisfactorily bendable with weak force or reaction force while maintaining overall rigidity.
In addition, as shown in Japanese Patent Publication No. 2003-90186 which the applicants of the present invention developed, the conventional shutter is sometimes formed by a flexible resin surface material and rigid resin core material together by two-material molding. However, the conventional shutter includes the above-mentioned problems as well.
The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide a door shutter which can satisfactorily maintain or improve the sliding characteristic and the exterior, while maintaining the overall rigidity, especially, no matter if the upper edges of the both inner side wall portions of the opening of the device have different heights, or the upper edges of both inner side wall portions of the opening of the installation portion attaching the device have different heights, or in spite of the curvature of the curve portion on a guide groove side.
Further objects and advantages of the invention will be apparent from the following description of the invention.